Device for applying and tightening the strings of tennis rackets



May 12, 1936. F. w. WHITESIDE 2,040,194

' DEVICE FOR APPLYING AND TIGHTENING THE STRINGS OF TENNIS RAGKETS Filed June 28. 1954 Mmsss Patented May 12, 1936 UNITED STATES PATENT OFFICE DEVICE FOR APPLYING AND TIGHTENING THE STRINGS OF TENNIS RACKETS 24 Claims.

This invention relates to a device for applying and tensioning the strings of tennis rackets and analogous implements having open head frames of various forms provided with suitable 5 apertures at regular intervals throughout their perimeters for receiving gut or similar strings, the latter being usually threaded continuously through the apertures back and forth across the space in intersecting lines, usually at right an- 10 gles to each other, and the main object of the present invention is to provide a more convenient and expeditious means for tensioning the string as it is successively threaded through the holes in the frame than has heretofore been practised and at the same time to enable the operator to secure a uniform tension of each section of the string as it is drawn across the opening in the frame.

One of the specific objects is to enable the de- 20 vice to be moved around and upon the frame from hole to hole as the strings are threaded therethrough and to place each string section under the desired tension as may be desired according to the length or position of the string 25 in the frame. 7

Another specific object is to effect the tensioning of the string sections through the medium of what may be termed a tensioning lever and an operating lever, both mounted upon the 30 carrier for relative movement about a common axis and to transmit motion from the operating lever to the tensioning lever through the medium of a compression spring or equivalent yielding member whereby the string may be tensioned 35 under a yielding force.

Other objects and uses relating to specific parts of the device will be brought out in the following description.

In the drawing:-

Figure 1 is a side elevation of my improved string-tensioning device and adjacent portion of a tennis racket upon which it is movably mounted, the levers being shown by full lines in their string-tensioning position, and the dotted lines indicating the position of the levers at the beginning or during the tensioning operation.

Figure 2 is an enlarged sectional view taken along line 2-2, Figure 1.

Figure 3 is a detail sectional view taken on line 33, Figure 2.

Figure 4 is a detail sectional view taken in the plane of line 44, Figure 1.

Figure 5 is an enlarged sectional view taken on 1 line 5-5, Figure 3,

Figure 6 is a perspective view of the detached tension-indicating spindle.

As illustrated, this device comprises a carrier I, a tension lever 2, and an operating lever 3, both of said levers being mounted upon the carrier I for relative movement about ,a common axis and are yieldingly connected to each other through the medium of a compression spring 4.

The carrier I is movable around and upon the perimeter of the open frame A of a tennis racket or similar implement and is provided with bearings members 5 and 5, the latter being provided with an extension 6 overlapping upon one side of the frame A, to guide the carrier in its movement around and upon said frame which latter is preferably held in a vise or similar clamp during the stringing operation.

Both of these levers 2 and 3 are preferably mounted co-axially upon a pivotal bolt I having one end threaded and engaged in a threaded opening 8 in the carrier I and its other end ex tended into a co-axial opening 9 in the tensioning lever 2, the intermediate portion of the bolt being provided with an annularenlargement I upon which is journaled the adjacent end of the operating lever 3.

The bolt 8 extends outwardly beyond the outer face of the upright portion of the carrier I and is provided with a lock nut II which, together with the enlarged annulus III, engage opposite faces of the carrier to firmly hold the bolt in fixed operative position upon the carrier against relative rotation.

The adjacent end of the operating lever 3 is interposed between the corresponding end of the tensioning lever 2 and inner face of the carrier I but is free to rock about the axis of the pivotal bolt 8 and is provided with peripheral ratchet teeth I2 for a purpose presently described.

The adjacent end of the string-tensioning 1ever 2 is also journaled upon the pivotal bolt 1 through the medium of ball bearings I3 and inner and outer collars I4 and I which are tightly fitted respectively upon the reduced end of the bolt I and within the hub of the lever 2, the object of which is to enable the lever 2 to rock about its axis with as little friction as possible.

The reduced end of the pivotal bolt I is provided with a slot I6 for receiving a screw driver or similar tool by which the bolt I may be screwed into the threaded opening 8. a

The adjacent end of the lever 2 is provide with-a hollow circular hubor drum I'I within which the collars I5 are tightly fitted to rotate therewith about the axis of the pivotal bolt I.

One end of the string as a with which the racket frame is to be equipped may be knotted in any suitable manner for securement to one side of the frame and has its other end wound one or more turns around and upon the periphery of the drum I1 and then attached to one or more anchor members I8 on the lever 2 between the drum and free end of said lever, as shown more clearly in Figures 1 and 2.

The levers 2 and 3 extend in the same general direction some distance to one side of the axis of the pivotal bolt 1, the lever 3 being of greater length than-the lever 2 and has its intermediate portion offset directly over the free end of the lever 2 and its free end provided with a handle 3' by which both levers may be rocked about the axis of the pivotal bolt I.

Tension indicator Suitable means is provided for indicating the amount of relative movement of the levers 2 and 3 during the string-tensioning operation and for this purpose one end of a spindle I9 is passed through an elongated opening I9 in the free end of the lever 2 and is connected thereto by means of a pivotal pin 20, the other or upper end of the spindle being extended through an enlarged opening'2I in the overlying portion of the lever 3 and is provided with graduations 22 representing units of force, such as pounds pressure or tension adapted to register with the upper face of the adjacent portion of the lever 3 to indicate the amount of tension applied to' strings a. The compression spring 4 is interposed between the upper face of the free end of the lever 2 and lower face of the overlying portion of the lever 3,'thereby constituting resilient means for transmitting motion from the operating lever 3 to the tension regulating lever 2.

A suitable holding pawl or detent 23 is pivoted at 24 to the carrier I for engaging the ratchet teeth I2 to hold the operating lever 3 in its adjusted position, said pawl being yieldingly held in engagement with the ratchet teeth by means of a spring 25, as shown more clearly in Figures 1, 3 and 5.

The upper end of the indicator spindle I9 is preferably somewhat larger than the opening 2| to prevent undue separation of the free ends of the levers 2 and 3 and thereby to prevent accidental displacement of the indicator pin from the lever 3.

When assembling the various parts of the device, the collars I4 are tightly pressed upon the reduced end of the pivotal bolt 1 while the collars I5 will also be tightly pressed within the hub I! of the lever 2, thus assembling the pivotal bolt upon said lever after whichthe pivotal bolt may be inserted through the alined opening I I! in the lever 3 and screwed into the upright portion of the carrier I with the shoulder I0 engaging the inner face of the carrier, after which the nut II may be screwed upon the outer end of the pivotal bolt to firmly lock the latter to the carrier against relative rotation or endwise movement, while permitting free rocking movement of both of the levers 2 and 3.

Operation When the string a has been anchored to one side of the frame A through the hole therein and extended through the alined opening in the opposite side, of the, frame, the carrier I will be placed in operative position upon the perimeter of the frame with its bearing members 5 and 5' at opposite sides of the hole through which the string is passed.

The levers 2 and 3 will then be rocked upwardly and rearwardly by means of the handle 3 to or beyond the position shown by dotted lines in Figure 1, whereupon the outer portion of the string will be wound one or more turns around the drum H and securely fastened to the anchor members I8, it being understood that the string will have been previously drawn as tightly as possible by hand.

When the string is wound around the drum and anchored in the manner described, the levers 2 and 3 will be rocked forwardly by means of the handle 3 toward the position shown by full lines in Figure 1, thereby causing the portion of the string previously threaded through the registering holes to be placed under more or less tension, which tension will be maintained by the engagement of the pawl 23 with the ratchet teeth I2 on the lever 3.

This tension of the string tends to retard the forward and downward movement of the lever 2 but a similar movement of the lever 3 may be continued along the spindle I9 and against the action of the spring 4 which will be placed under compression as the movement of the lever 3 continues, thereby effecting a yielding forward and downward pressure upon the free end of the lever 2 to further tension the string a according to the resistance under which the compression spring 4 is placed, thus forcing the lever 2 to its string-tensioning position under the yielding pressure of the spring 4 through the continued forward and downward movement of the lever 3.

It is now clear that as the string is placed under tension by the forward and downward movement of the lever 2 and similar movement of the lever 3, a similar movement of the lever 3 may be continued along the graduated spindle I9 against the the action of the spring 4, thereby gradually increasing the resistance of the latter until the string is placed under the desired tension as indicated by the graduations on said spindle registering with the upper face of the lever 3.

When the string is placed under the desired tension, an awl or similar tool may be wedged into the hole through which the string is passed and against said string sufliciently to hold the string against relaxing its tension, whereupon the remaining portions of the string may be detached from the anchors I8 and drum I! and rethreaded through the next succeeding registering holes in the opposite sides of the frame A.

The tensioning device will then be moved around and upon the periphery of the frame A into position to be engaged by the free portion of the same string which will then be rewound upon the drum I1 and attached to the anchor members I8 in the manner previously explained ready for a repetition of the tensioning operation upon the second section of the string.

These operations are repeated for each section of the string as it is tensioned across the opening of the frame and as each section is brought to the desired tension the awl previously inserted is removed and reinserted into the last hole through which the string is passed to hold said string under the produced tension, the repetition of the operations being continued until all of the strin sections are placed in operative position and brought to the desired tension indicated by the graduations on the spindle I9;

The device described is particularly simple, expeditious and reliable as to the tension desired and affords the user a convenient means for restringing the tennis frame when necessary or desired, but it is evident that some change may be made in the detail construction without departing from the spirit of the invention.

What I claim is:

l. A device for tensioning the strings of tennis rackets comprising a carrier adapted to be received upon the frame of the racket, co-axial members mounted on the carrier and relatively movable about a common axis, means for attaching the string to one of said members for tensioning the same as the member is moved in one direction, the other member being manually movable about said axis, and yielding means for transmitting motion from the second member to the first member for tensioning the string under gradually increasing force.

2. A device for tensioning the strings of tennis rackets comprising a carrier adapted to be received upon the frame of the racket, co-axial -members mounted on the carrierand relatively movable about a common axis, means for attaching the string to one of said members for tensioning the same as the member is moved in one direction, the other member being manually movable about said axis, yielding means for transmitting motion from the second member to the first member for tensioningthe string under gradually increasing force, and means for locking said device when a predetermined tension has been placed upon the string to retain the string tensioned at the predetermined amount.

3. A device for tensioning the Strings of tennis rackets comprising a carrier adapted to be received upon the frame of the racket, a drum member rotatively mounted on said carrier around which the string is adapted to be wound, a second member movable about the axis of the drum, and yielding means for transmitting motion from the second member to the first member to wind the string thereon.

4. A device for tensioning the strings of tennis rackets comprising a carrier adapted to be received upon the frame of the racket, a string-tensioning member pivotally mounted on the carrier and provided with means for attaching the string thereto, an operating member for the first member, and spring means for transmitting motion from the second member to the first member for tensioning the string under yielding pressure.

5. A device for tensioning the strings of tennis rackets comprising a carrier adapted to be received upon the frame of the racket, a stringtensioning member pivotally mounted on the carrier and provided with means for attaching the string thereto, an operating member for the first member, spring means for transmitting motion from the second member to the first member for tensioning the string under yielding pressure, and means on one of the members movable relatively to the other member for indicating the amount of tension applied to the string during the tensioning operation.

6. A tennis racket stringing device comprising a carrier adapted to be received upon the racket frame, co-axial members mounted on said carrier and relatively movable about their axis, one of said members being movable by hand, yielding means for transmitting motion from the lastnamed member to the other member, and a drum on the other member co-axial 'therewith and around which the string is adapted to be wound,

said drum being actuated by the movement of the-other member about its axis for tensioning the string.

7. In a small hand-operated device for tensioning the strings of tennis rackets or the like wherein the racket during the stringing operation is held in a vise or similar device and Wherein the string is anchored at one side of the racket frame and extends through an aperture formed on the other side of the racket frame, a supporting member adapted to be applied to the frame while the frame is held in the vise, a string tensioning member carried by said supporting member to which the string is secured, means for moving said string tensioning member a desired amount to place a desired amount of tension on the string, and means for retaining said string-tensioning member in said position to retain the desired tension on the string whereby manual control of the device may be removed to enable a tool to be inserted in said aperture so as to hold the string in tautened condition while the string is removed from said tensioning device.

8. In a small hand-operated device for tensioning the strings of tennis rackets or the like wherein the racket is held during the stringing operation in a vise or similar device, a supporting member adapted to be applied to the frame of the racket while the frame is held in the vise, a string-tensioning member carried by said supporting member to which the string is secured, manually operated means, means for transmitting pressure from said manually operated means to said string-tensioning member for tensioning the string, and latch means engageable with said manually operated means for retaining the said manually operated member in any desired position to retain the string at any predetermined tension.

9. In a device for tensioning the strings of tennis rackets or the like, a supporting member adapted to be applied to the frame of the racket a string-tensioning member carried by said supporting member and to which the string is $6- cured, manually operated means, spring means between said manually operated means and said string-tensioning member whereby pressure exerted on said manually operated means is yieldingly transmitted to said string-tensioning member for tensioning the string, and means for retaining said manually operated means in a predetermined position to retain the string at a predetermined tension.

' 10. In a device for tensioning the strings of tennis rackets or the like, a supporting member adapted to be applied to the frame of the racket, a string-tensioning member carried by said supporting member and to which the string is secured, a manually operated member, spring means for transmitting motion from said manually operated member to said string-tensioning member for tensioning the string under yielding pressure, means on one of said members movable relatively to the other member for indicating the amount of tension applied to the string during the tensioning operation, and means for retaining said string-tensioning member in a fixed position when the desired amount of tension has been placed upon the string.

11. In a small hand-operated device for tensioning the strings of tennis rackets or the like wherein the racket during the stringing operation is held in a vise or similar device and wherein the string isanchored on one side of the racket frame and extends through an aperture formed on the other side of the racket frame, a support- ,ing member adapted to be loosely applied to the frame with portions thereof on opposite sides of said string longitudinally of the frame, a. string- :tensioning member carried by said supporting member to which the string is secured, means for moving said string-tensioning member a desired amount to place a desired amount of tension on the string, and means for retaining said string-tensioning member in said position to retain the desired tension on the string whereby manual control of the device may be removed to enable a tool to be inserted in said aperture so as to hold the string in tautened condition while the string is removed from said tensioning device.

12. In a device for tensioning the strings of tennis rackets and the like, a supporting member having portions thereof engaging the frame on opposite sides of the aperture in the rim of the racket through which the string extends, a string-tensioning member carried by the supporting member to which said string is secured, manually operated means, and spring means for transmitting motion from said manually operated member to said string-tensioning member for tensioning the string under yielding pressure.

13. In a device for tensioning strings of tennis rackets or the like wherein the string is anchored at one side of the racket frame and extends through an aperture formed on the other side of the racket frame, a supporting member having portions thereof straddling the aperture in the racket frame through which the string extends and having sufiicient bearing on the racket frame to stabilize it thereon, and a string tensioning member carried by the supporting member and to which the string is secured, said string-tensioning member being movable to tension the string, the strain of the string being transmitted to said supporting member so that the pull thereof is applied on the supporting member so as to bind said supporting member rigidly on the racket frame.

14. In a device for tensioning strings of tennis rackets or the like wherein the string is anchored at one side of the racket frame and extends through an aperture formed on the other side of the racket frame, a supporting member having portions thereof straddling the aperture in the racket frame through which the string extends and having sufficient bearing on the racket frame to stabilize it thereon, a string-tensioning member carried by the supporting member to which the string is secured, and manually operated means for moving said string-tensioning member to tension the string, the strain of the string being transmitted to said supporting member so that the pull thereof is applied on the supporting member so as to bind said supporting member rigidly on the racket frame.

15. In a device for tensioning strings of tennis rackets or the like wherein the string is anchored at one side of the racket frame and extends through an aperture formed on the other side of the racket frame, a supporting member having portions thereof engaging the racket the supporting member so as to bind said supporting member rigidly on the racket frame, and means for retaining said string-tensioning member in a position such that a predetermined tension is retained on the string without manual effort.

16. In a device for tensioning the strings of tennis rackets or the like in which the string is anchored at one side of the racket frame and extends through an aperture formed on the other side of the racket frame, a supporting member having portions thereof straddling the aperture in the racket frame through which the string extends and having sufficient bearing on the racket frame to stabilize it thereon, a string-tensioning member carried by the supporting member to which the string is secured, manually operated means, a spring for transmitting motion from said manually operated means to said stringtensioning member to tension the string under yielding pressure, the strain of the string being transmitted to said supporting member so that the pull thereof is applied on the supporting member so as to bind said supporting member rigidly to the racket frame, and means for retaining said spring under a predetermined tension so as to retain the string under a predetermined tension.

17. In a device for tensioning the strings of tennis rackets or the like in which the string is anchored at one side of the racket frame and extends through an aperture formed on the other side of the racket frame, a supporting frame having portions thereof straddling the aperture in the racket frame, a string-tensioning member carried by the supporting frame to which the string is secured, a manually operated member carried by the supporting frame, a spring for transmitting motion from said manually operated member to said string-tensioning member for tensioning the string under yielding pressure. means on one of said members movable relatively to the other of said members for indicating the amount of tension applied to the string during the tensioning operation, and means for locking said manually operated member to said supporting frame so as to retain the desired tension on the string.

18. A device for tightening racket strings including a relatively fixed fulcrum in the form of a saddle member to be applied to the racket frame and manually operable string tightening means pivotally mounted on said fulcrum and adapted to be engaged by the string to be tightened, whereby the string is always pulled substantially in alignment with the string hole in the racket frame upon pivoting of said tightening means.

19. In a small hand-operated device for tensioning the strings of rackets wherein the racket during the stringing operation is held in a vise or similar device and wherein the string is held at one side of the racket frame and extends through an aperture formed on the other side of the racket frame, a supporting member adapted to be applied to the racket frame while the frame is held in the vise, a string tensioning member operatively connected to the supporting member and to which the string is secured, and

means for moving the string tensioning member to apply tension to the string, the attachment of the string to the string tensioning member and the direction of pull on the string being such that the string is always pulled substantially in alignment with the aperture when the and to which the string is secured, said string tensioning member being positioned with respect to the racket frame and having the string secured thereto in a manner such that a force exerted on the string tensioning member is applied on the string along the axis of the aperture, a hand operated member, and means including a spring through which a force applied on said hand operated member is transmitted to said string tensioning member.

21. In a small hand-operated device for tensioning the strings of rackets wherein the racket during the stringing operation is held in a vise or similar device and wherein the string is held at one side of the racket frame and extends through an aperture on the other side of the racket frame, a supporting member adapted to be applied to the racket frame while the frame is held in the vise, said supporting member having portions in contact with the racket frame longitudinally of the rim thereof and on opposite sides of the string, a string tensioning member operatively connected to the supporting member and to which the string is secured, and means for applying a force on the string tensioning member and moving it to tauten the string, the force being directed by said string tensioning member along the axis of the aperture.

22. In a device for tensioning the strings of rackets wherein the string is held at one side of the racket frame and extends through an aperture on the other side of the racket frame, a supporting member adapted to be applied to the racket frame, said supporting member having portions thereof straddling the aperture through which the string extends, a string tensioning member operatively connected to the supporting member and to which the string is secured, the string being secured to said string tensioning member in a manner such that a force exerted on the string tensioning member is applied on the string along the axis of the aperture, a hand operated member, means including a spring through which a force applied on said hand operated member is transmitted to said string tensioning member, and a latch for retaining the string tensioning member with the string at a pre-determined tension whereby both hands may be removed from the device and the string retained at said pre-determined tension.

23. In a device for tensioning the strings of rackets wherein the string is held at one side of the frame and extends through an aperture on the other side of the racket frame, a supporting member adapted to be applied to the racket frame, said supporting member having portions in contact with the frame longitudinally of the rim thereof and on opposite sides of the string, a string tensioning member operatively connected to the supporting member and to which the string is secured, means including a spring for applying a force on the string tensioning member to move said string tensioning member to tauten the string, the force being directed by said string tensioning member along a line in alignment with the axis of the aperture, the tension of said string tending to bind the supporting member tightly to the frame of the racket, and a latch for holding the string tensioning member in a pre-determined position whereby a pre-determined tension is retained on the string.

24. In a device for terrsioning the strings ofrackets wherein the string is held at one side of the racket frame and extends through an aperture on the other side of the racket frame, a supporting member adapted to be applied to the racket frame, said supporting member having portions thereof straddling the aperture through which the string extends, a string tensioning member operatively connected to said supporting member and to which the string is secured, a hand operated member, a spring interposed between said hand operated member and said string tensioning member through which force applied on said hand operated member is transmitted to said string tensioning member, means for indicating the force applied on the spring and thereby the tension of the string, said string tensioning member being positioned with respect to the racket frame and having the string secured thereto in a manner such that the force transmitted to said string tensioning member is applied on the string along the axis of the aperture and the tensioning of the string tends to bind the supporting member tightly to the racket frame, and latch means for retaining the string tensioning member with the string at a pre-de- F termined tension whereby both hands of the operator may be removed from the device to enable convenient insertion of an awl in the aperture for retaining the string at said pre-determined tension while the string is removed from said string tensioning member.

FREDERICK W. WHITESIDE. 

